docs: def add_nodes(self, node_name_list, dataframe=False):
          """
          Add new nodes to the network
  
          :param node_name_list: list of node names, e.g. ['a', 'b', 'c']
          :param dataframe: If True, return a pandas dataframe instead of a dict.
          :return: A dict mapping names to SUIDs for the newly-created nodes.
          """
          res = self.session.post(self.__url + 'nodes', data=json.dumps(node_name_list), headers=HEADERS)
          check_response(res)
          nodes = res.json()
          if dataframe:
              return pd.DataFrame(nodes).set_index(['SUID'])
          else:
              return {node['name']: node['SUID'] for node in nodes}